Integrated insulin delivery system having safety features to prevent hypoglycemia
Safety features are applied to an integrated insulin delivery system to enhance safety by controlling medication delivery including the automatic resumption of basal rate after a particular event, such as termination of a bolus, expiration of a time period, delayed resumption after the bolus has terminated, IOB comparison, and others. Other safety features include overriding a delivery control that may result in hypoglycemia, and terminating an extended bolus or temporary basal rate in view of a glucose signal indicating imminent carbohydrate deficiency. In another feature, an automatic resumption of a basal delivery rate is programmed into the delivery device to avoid the possibility of complete loss of delivery of insulin in the event that communication with the delivery device is disrupted.
1. A method comprising:
delivering a bolus of insulin to a user using an integrated insulin delivery system, the system comprising:
a continuous glucose sensor configured to provide a glucose level signal representative of sensed glucose;
an insulin delivery device configured to deliver insulin in response to delivery control signals at a programmed basal rate and as a bolus; and
a controller programmed to receive the sensor glucose level signal and to provide a delivery control signal to the insulin delivery device to deliver the bolus of insulin and to set the programmed basal rate to zero for a predetermined period of time after commencement of the delivering.
2. The method of claim 1 , wherein the predetermined period of time is based on an amount of insulin delivered in a preceding closed-loop cycle.
3. The method of claim 1 , wherein the predetermined period of time is based on a level of insulin on board (IOB) and the programmed basal delivery rate.
4. The method of claim 1 , wherein the bolus of insulin is an instantaneous bolus of insulin.
5. The method of claim 1 , wherein the bolus of insulin is an extended bolus of insulin.
6. The method of claim 5 , wherein the controller is further programmed to interrupt the extended bolus of insulin.
7. The method of claim 5 , wherein the controller is further programmed to interrupt the extended bolus of insulin if the user is in a carbohydrate deficient state.
8. The method of claim 1 , wherein the continuous glucose sensor and the insulin delivery device are at least partially implanted within the user.
9. A method comprising:
delivering a bolus of insulin to a user using an integrated insulin delivery system, the system comprising:
a continuous glucose sensor configured to provide a glucose level signal representative of sensed glucose;
an insulin delivery device configured to deliver insulin in response to delivery control signals at a programmed basal rate and as a bolus; and
a controller programmed to receive the sensor glucose level signal and to provide a delivery control signal to the insulin delivery device to deliver the bolus of insulin and to set the programmed basal rate to zero for a predetermined period of time.
10. The method of claim 9 , wherein the predetermined period of time is based on an amount of insulin delivered in a preceding closed-loop cycle.
11. The method of claim 9 , wherein the predetermined period of time is based on a level of insulin on board (IOB) and the programmed basal delivery rate.
12. The method of claim 9 , wherein the bolus of insulin is an instantaneous bolus of insulin.
13. The method of claim 9 , wherein the bolus of insulin is an extended bolus of insulin.
14. The method of claim 13 , wherein the controller is further programmed to interrupt the extended bolus of insulin.
15. The method of claim 13 , wherein the controller is further programmed to interrupt the extended bolus of insulin based on if the user is in a carbohydrate deficient state.
16. The method of claim 9 , wherein the continuous glucose sensor and the insulin delivery device are at least partially implanted within the user.
17. A method comprising:
receiving a sensor glucose level signal representative of sensed glucose with a controller, the sensor glucose level signal received from a continuous glucose sensor;
providing, using the controller, a delivery control signal to an insulin delivery device based on the sensor glucose level signal,
wherein the delivery control signal signals the insulin delivery device to deliver a bolus of insulin and to set a programmed basal rate to zero for a predetermined period of time.
18. The method of claim 17 , further comprising delivering the bolus of insulin to a user with the insulin delivery device.
19. The method of claim 18 , wherein the predetermined period of time is after commencement of the delivering.
20. The method of claim 17 , wherein the continuous glucose sensor and the insulin delivery device are at least partially implanted within the user.